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+/* Copyright (C) 1998, 2000, 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include <kernel-features.h>
+
+#define EINVAL 22
+
+ .text
+
+ENTRY (__mmap)
+# ifdef __ASSUME_MMAP2_SYSCALL
+ /* This code is actually a couple of cycles slower than the
+ sys_mmap version below, so it might seem like a loss. But the
+ code path inside the kernel is sufficiently much shorter to
+ make it a net gain to use mmap2 when it's known to be
+ available. */
+
+ /* shuffle args */
+ str r5, [sp, #-4]!
+ ldr r5, [sp, #8]
+ str r4, [sp, #-4]!
+ ldr r4, [sp, #8]
+
+ /* convert offset to pages */
+ movs ip, r5, lsl #20
+ bne .Linval
+ mov r5, r5, lsr #12
+
+ /* do the syscall */
+ swi SYS_ify (mmap2)
+
+ /* restore registers */
+2:
+ ldr r4, [sp], #4
+ ldr r5, [sp], #4
+
+ cmn r0, $4096
+ RETINSTR(cc, lr)
+ b PLTJMP(syscall_error)
+
+.Linval:
+ mov r0, #-EINVAL
+ b 2b
+# else
+ /* Because we can only get five args through the syscall interface, and
+ mmap() takes six, we need to build a parameter block and pass its
+ address instead. The 386 port does a similar trick. */
+
+ /* This code previously moved sp into ip and stored the args using
+ stmdb ip!, {a1-a4}. It did not modify sp, so the stack never had
+ to be restored after the syscall completed. It saved an
+ instruction and meant no stack cleanup work was required.
+
+ This will not work in the case of a mmap call being interrupted
+ by a signal. If the signal handler uses any stack the arguments
+ to mmap will be trashed. The results of a restart of mmap are
+ then unpredictable. */
+
+ /* store args on the stack */
+ stmdb sp!, {a1-a4}
+
+ /* do the syscall */
+ mov a1, sp
+ swi SYS_ify (mmap)
+
+ /* pop args off the stack. */
+ add sp, sp, #16
+
+ cmn r0, $4096
+ RETINSTR(cc, lr)
+ b PLTJMP(syscall_error);
+#endif
+
+PSEUDO_END (__mmap)
+
+weak_alias (__mmap, mmap)